ISB

Instruction Synchronization Barrier flushes the pipeline in the PE and is a context synchronization event. For more information, see Instruction Synchronization Barrier (ISB).

313029282726252423222120191817161514131211109876543210
11010101000000110011CRm11011111
opcRt

ISB {<option>|#<imm>}

// No additional decoding required

Assembler Symbols

<option>

Specifies an optional limitation on the barrier operation. Values are:

SY
Full system barrier operation, encoded as CRm = 0b1111. Can be omitted.

All other encodings of "CRm" are reserved. The corresponding instructions execute as full system barrier operations, but must not be relied upon by software.

<imm>

Is an optional 4-bit unsigned immediate, in the range 0 to 15, defaulting to 15 and encoded in the "CRm" field.

Operation

InstructionSynchronizationBarrier(); if IsFeatureImplemented(FEAT_BRBE) && BRBEBranchOnISB() then BRBEISB();


Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45

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